Recently, with the miniaturization technique of semiconductor devices, a market of large capacity non-volatile memory systems with levity, fast access and low power consumption has been expanded substantially. Accordingly, from the aspect of security, information management of large capacity memory system is given great importance.
Furthermore, with the miniaturization of non-volatile memories, production variability in characteristics of elements has grown progressively large. Although production variability of non-volatile memories depends on various factors, one of the known factors is a factor that originates from factory-determined processes. Because the process-induced production variability includes random physical features, it is difficult to reproduce memories with the same physical feature.